Here is a link to the
Mandrake network setup documentation. Are the cards just recognized or actually set up?
Did you set up the network connection during the installation?
Are you using a dynamic or static internet connection?
What onboard NIC is in the system? If you don't know, what motherboard are you using? This will help sort out what NIC to use.
If you did set up the network during the install, on boot, as you see the messages scrolling by, you should see something like;
eth0............
If you see the message etho......failed
the card is not set up properly yet.
Once we know more information, we can go on and help to get the connection going.